OK. I saw that you already developed the plugin. Note that in the post below, I updated the information several times after I originally posted. If you have a 51GB THETA Z1 in Japan, you need to fill out an extra form if the camera you are using requires client mode.
If you’re still having problems with the Z1 and it works on the V, post the error message and the API you’re using in the camera (WebAPI or CameraAPI).